In the cleaning industry there is a need to handle a wide range of liquid chemical, including alkalis, detergents, bleaches, acids and the like. These chemicals have a variety of viscosities and concentrations requiring dilution, usually with water, before use.
In use, the specific proportions of the various chemicals delivered must be controlled for efficiency, performance, repeatability and low cost. If air leaks into any fluid flow stream, the air will cause fluid flow measurement errors as the air travels through the flow meters. These errors will result in improper proportions of the delivered liquid mixture. Such air leakage into the flow measurements is a limitation of the presently available liquid mixture delivery systems.
As referenced above, the introduction of air into the prior art systems results in non-uniform fluid mixtures and, ultimately, in poor cleaning performance.
An object of this invention is to produce a system where volumes of fluid chemical additives are reliably achieved even with air volumes being introduced into the system.
Another object of this invention is to stop the dispensing system when an air leak occurs that cannot be automatically corrected.
It is a further object of this invention to provide a system with fewer service requirements and long life.